Exodus 28:25-28

²⁵You shall put the other two ends of the two cords on the two filigree settings, and put them on the shoulder pieces of the ephod, at the front of it. ²⁶And you shall make two rings of gold and place them on the two ends of the breastpiece, on the edge of it, which is toward the inner side of the ephod. ²⁷And you shall make two rings of gold and put them on the bottom of the two shoulder pieces of the ephod, on the front of it close to the place where it is joined, above the skillfully woven band of the ephod. ²⁸And they shall bind the breastpiece by its rings to the rings of the ephod with a violet cord, so that it will be on the skillfully woven band of the ephod, and that the breastpiece will not come loose from the ephod.